Implement some of the missing LFS64 support.

This gives us:

* <dirent.h>
  struct dirent64
  readdir64, readdir64_r, alphasort64, scandir64

* <fcntl.h>
  creat64, openat64, open64.

* <sys/stat.h>
  struct stat64
  fstat64, fstatat64, lstat64, stat64.

* <sys/statvfs.h>
  struct statvfs64
  statvfs64, fstatvfs64.

* <sys/vfs.h>
  struct statfs64
  statfs64, fstatfs64.

This also removes some of the incorrect #define hacks we've had in the
past (for stat64, for example, which we promised to clean up way back
in bug 8472078).

Bug: 11865851
Bug: 8472078
Change-Id: Ia46443521918519f2dfa64d4621027dfd13ac566
diff --git a/libc/include/sys/statvfs.h b/libc/include/sys/statvfs.h
index e910c03..3d8179e 100644
--- a/libc/include/sys/statvfs.h
+++ b/libc/include/sys/statvfs.h
@@ -23,19 +23,21 @@
 
 __BEGIN_DECLS
 
-struct statvfs {
-  unsigned long f_bsize;
-  unsigned long f_frsize;
-  fsblkcnt_t    f_blocks;
-  fsblkcnt_t    f_bfree;
-  fsblkcnt_t    f_bavail;
-  fsfilcnt_t    f_files;
-  fsfilcnt_t    f_ffree;
-  fsfilcnt_t    f_favail;
-  unsigned long f_fsid;
-  unsigned long f_flag;
-  unsigned long f_namemax;
-};
+#define __STATVFS64_BODY \
+  unsigned long f_bsize; \
+  unsigned long f_frsize; \
+  fsblkcnt_t    f_blocks; \
+  fsblkcnt_t    f_bfree; \
+  fsblkcnt_t    f_bavail; \
+  fsfilcnt_t    f_files; \
+  fsfilcnt_t    f_ffree; \
+  fsfilcnt_t    f_favail; \
+  unsigned long f_fsid; \
+  unsigned long f_flag; \
+  unsigned long f_namemax; \
+
+struct statvfs { __STATVFS64_BODY };
+struct statvfs64 { __STATVFS64_BODY };
 
 #define ST_RDONLY      0x0001
 #define ST_NOSUID      0x0002
@@ -48,7 +50,9 @@
 #define ST_RELATIME    0x1000
 
 extern int statvfs(const char* __restrict, struct statvfs* __restrict) __nonnull((1, 2));
+extern int statvfs64(const char* __restrict, struct statvfs64* __restrict) __nonnull((1, 2));
 extern int fstatvfs(int, struct statvfs*) __nonnull((2));
+extern int fstatvfs64(int, struct statvfs64*) __nonnull((2));
 
 __END_DECLS